In many electrical systems, energy is delivered using alternating current (AC). Most homes and buildings, for example, use AC power supplies to provide energy to various systems within the structure, such as air conditioning, heaters, refrigeration personal electronics, and lighting. As the cost of electricity generation and concerns over its associated environmental damage increases, there is a substantial interest in increasing the efficiency of electricity delivery to homes and business. Even a modest improvement in efficiency can be of significant benefit to the resident as well as the environment.
Electricity delivery systems are not perfectly efficient. In many cases, the electricity supply is dirty and may include noise or other artifacts that can cause inefficient transfer of energy from the supply to the load. The noise may be generated at the facility where the electricity is generated, during distribution, or due to anomalies in the transmission lines that carry the electricity. In most cases, power supply companies attempt to generate a clean power signal, but some amount of noise is inevitable.
An electricity supply may also include anomalies such as power spikes or picks that represent a large amount of energy delivered over a short period of time. Unlike noise, which may often be random or fuzzy, power spikes represent a severe but temporary deviation from the normal sinusoidal pattern of an AC electrical signal. Although a single spike may not be particularly destructive (though it is certainly possible), multiple spikes delivered to a machine or component over an extended period of time may cause significant damage or possibly failure of the device. Of course, in any situation where an electrical component fails, the potential for personal injury is always present.
A clean electricity supply is one that minimizes an amount of noise and other anomalies delivered to the load. Clean electricity supplies generally allow more efficient and safe operation of electronic devices and provide significant benefits to devices incorporating electric motors or that include other inductive loads. Furthermore, the additional electrical energy that would otherwise be consumed in unnecessary noise or spikes is preserved in a clean electricity supply.
In electrical systems it is possible to combine multiple electrical signals into a single signal for delivery to a load. When the multiple signals combine, they may do so constructively or destructive, referred to as either constructive or destructive interference. In an electrical system that includes noise, for example, it is possible to combine a supplementary electrical signal with a noisy power signal to cancel the noise and generate a clean power signal. In that case, the shape of the supplementary signal is selected to destructively interfere with the noise in the power signal to generate the clean signal. A similar mechanism, or one that employs capacitors to absorb additional electrical energy over short time periods may be used to combat power spikes or picks.
There is a need, therefore, for a system and method to compensate for noise, spikes, and other anomalies present in electrical energy supply signals to improve an efficiency and operation of loads driven by those electrical signals. Not only would such a system and method generate considerable cost savings and minimize damage to electrical systems, the system and method would minimize an amount of energy consumed mitigating the negative effects of power generation on the environment.